Overcarbonated bottles

[ebbytempura]

Hi, I'm a brewer in the Philippines. Just opened some bottles from a batch (500 bottles) that has been bottle conditioning for 5 days at 28 C. When opened slightly warm (25 - 28 C), the beer foams up within 10 seconds - not gushing and tastes normal except very bubbly. When cold (8 - 12 C), no foaming takes place for at least 5 minutes. When I pour out said beers, there is a huge amount of foam produced - can fill more than half the glass if I'm not careful with pouring.

I suspect it is an overcarbonation issue. Is there any way to fix carbonation once an entire batch of beer has been bottled?

[TL Services]

Rather than over-carbonation, this sounds more likely to be simply caused by the fact that at higher temperatures gases are less soluble than at low temperatures.

So, when you open a bottle at 28 C, the dissolved CO2 will come out of solution very easily compared to the lower temperature.

Pouring into a glass will simply speed up the CO2 coming out, as the surface (especially if that is also warm) will act as one big nucleation point for bubbles.

[gitchegumee]

In a perfect world...

You would have a Zahm to measure the exact carbonation level. But you won't likely have one. If it is overcarbonation due to priming the beer too much, then the only way to fix what you have is to cool even more to lower the saturation pressure so that you can pour into a very cold, wet glass. This will reduce foaming. Or you could use a degorging technique as in Champagne and rid sediment at the same time that you lower your carbonation slightly. Not for the feint of heart. If you're doing this commercially, then I'd suggest giving up the priming technique and counterpressure bottle, or use less priming sugars next time. BTW, where are you in PI?

[ebbytempura]

Rather than over-carbonation, this sounds more likely to be simply caused by the fact that at higher temperatures gases are less soluble than at low temperatures.

So, when you open a bottle at 28 C, the dissolved CO2 will come out of solution very easily compared to the lower temperature.

Pouring into a glass will simply speed up the CO2 coming out, as the surface (especially if that is also warm) will act as one big nucleation point for bubbles.

Yeah, this is exactly what I observed. Even a careful pour yields a really bubbly beer in the glass.

[ebbytempura]

You would have a Zahm to measure the exact carbonation level. But you won't likely have one. If it is overcarbonation due to priming the beer too much, then the only way to fix what you have is to cool even more to lower the saturation pressure so that you can pour into a very cold, wet glass. This will reduce foaming. Or you could use a degorging technique as in Champagne and rid sediment at the same time that you lower your carbonation slightly. Not for the feint of heart. If you're doing this commercially, then I'd suggest giving up the priming technique and counterpressure bottle, or use less priming sugars next time. BTW, where are you in PI?

I don't think I can afford a Zahm. I think I'll try disgorging just to see how it works, but I don't think it works for commercial production...looks quite tedious. I might be able to counter pressure fill soon once I get my hands on kegs. It's quite difficult to get brewing equipment out here.

I'm based in Manila. Started brewing a few months back.

[TL Services]

Yeah, this is exactly what I observed. Even a careful pour yields a really bubbly beer in the glass.

Try cooling bottles in a fridge, so they are around 3 deg C (typical domestic fridge is 3-5 deg C) and pour once they are fully cold. Also, when pouring:

- Cool the glass to reduce the temperature increase when the beer hits;
- Use a good glass-wash for glasses, as it's not unknown for detergents to leave deposits on the glass that can promote excessive foaming.